During the days 20 and May 21 there was another step of the program, the Critical Design Review (CDR). In this case it was held in the Netherlands, in the European Centre for Space Research and Technology Centre (ESTEC), that is to say, in the same place that the Selection Workshop was held.

This time, the system of work was similar to the Preliminary Design Review with some new features like the fact of gathering only BEXUS teams. On the one hand, a soldering course with the participation of one member of each team was developed during the 18th and 19th. Later, during the 20th and 21 the rest of participants were incorporated into the development of the CDR. This was the last time that the teams faced to a whole panel of experts, by a round of questions and a thorough review of the experiment.